Hair treatment, including hair coloring, is an ancient art. The oldest available records show that women then, as now, were not satisfied with their natural hair coloring and used available materials in an attempt to obtain a hair color which they considered more desirable than nature had provided. Among other coloring materials that were used anciently are henna, a red vegetable dye; indigo; sage; and camomile. Dark haired women in the time of Rome's zenith, who admired the blood hair of female slaves brought from northern Europe, used saffron, red arsenic, nut shells and plant ash to bleach their hair. Later it was found that if the hair was wet with soap and exposed to the sun it would lighten. Mixtures of alum, black sulfur and honey have also been used as lightening agents. In the latter part of the 19th century synthetic dyes, particularly paraphenylenediamine, were developed and offered for hair coloring, either alone or in admixture with metallic salts. Oxidizing agents, particularly hydrogen peroxide, came into rather widespread use as the bleaching agent to lighten hair.
Until relatively recent times little was known and understood about the structure of hair and the mechanics of hair coloring. Through microscopic study of the hair it has been determined that a typical hair shaft, the part of the hair outside the hair follicle where the hair is formed, comprises an outer sheath of scales called the cuticle, the main body of the hair called the cortex and a slender central filament called the medulla.
The scales of the cuticle are plate-like in shape and cover the cortex somewhat in the same general manner that shingles cover the roof where the root of the hair corresponds to the ridge and the end of the hair corresponds to the eaves. This arrangement of the scales permits the hair to be combed from the scalp outward without damage to the cuticle, just as water can flow down a roof that is well shingled without causing leakage, whereas brushing or combing the hair toward the scale tends to damage the cuticle just as a stream of water directed upwardly on a roof could easily cause leakage by penetration between the shingles and, if the force of the upwardly directed stream is strong enough, the shingles could be lifted and even torn from the roof. Being transparent, and colorless, the scale cells of the cuticle are not altered in color by bleaching agents but they must be altered structurally so as to permit the coloring solutions to pass through the cuticle and penetrate the cortex and the cuticle may be subjected to damage if the treating liquids are improperly used.
The cortex is composed of elongated cells, rather typical of fibers, comprised of complex proteins among which all the pigments that give the hair its color are found. Pigments are of different colors, such as yellow, red, brown, black, etc., and in general a hair shaft will contain pigment cells of several different colors. Pigments of different colors are affected differently by bleach and lightening solutions. In general such solutions attack the darker colors first and it has been found useful to divide the bleaching or lightening process from black to very light hair in stages which are referred to as follows:
Stage 1--black PA1 Stage 2--brown PA1 Stage 3--red PA1 Stage 4--red-gold PA1 Stage 5--gold PA1 Stage 6--yellow PA1 Stage 7--pale yellow PA1 Stage 8--white PA1 Bleaching and lightening liquids, however, affect not only the pigment cells but also other cells of the hair and some chemical bleachants under some conditions may have a variety of adverse effects on the structural part of the hair, e.g., seriously weaken or embrittle the hair so that it will break off in wet or dry condition; cause hair to lose its normal springiness or resilience when highly bleached (to Stage 7 or 8) so that in wet condition it feels like sponge or rubber, will stretch like a thin rubber filament if pulled, will break if stretched beyond the elastic limit, and in dry condition it is brittle and snaps off if bent; and reduce the ability of the hair to take up color in the normal manner. In many cases the scalp may also be deleteriously affected by contact for too long a period of time with the bleachants used on the hair. PA1 (a) in two operations which are frequently referred to as (1) bleaching or prelightening and (2) tinting, toning, or coloring, or PA1 (b) in some cases, in a single operation which comprises bleaching or ightening the natural pigments and simultaneously depositing other pigments in the cortex of the hair. PA1 (a) a single material which is normally liquid within the temperature range used for hair treating, PA1 (b) a solution of one or more materials in a liquid vehicle, including coloidal solutions, emulsions of one liquid in another, or PA1 (c) suspensions of a finely divided solid material in a carrier liquid. It is this type with which the present invention is more particularly concerned.
The medulla is not always present and is of little importance in coloring and otherwise treating the hair.
Hair coloring of the permanent type as practiced today may be carried out
The one step process was not introduced in the market place until about 1950 after which it became very popular but it has not completely displaced the two step process which is still necessary if a person desires to change the color of the hair through several stages of lightening.
Permanent hair coloring is somewhat of a misnomer because no known process of hair coloring is able to affect the natural color of new hair that grows out after a so-called permanent color is applied. The word "permanent" as used i this art means only that the color which is applied to the then existing shaft of the hair is not washed out with shampoo and water. The most popular way of obtaining permanent hair coloring is by the use of penetrating tints or dyes which deposit pigment in the cortex of the hair shaft. It is possible, however, to apply a coating tint on the cuticle layer but this produces an unnatural look that most persons consider far less satisfactory than the appearance obtained by the use of a penetrating tint.
Semipermanent hair coloring differs from the permanent type in that it will wash out but requires several shampooings before all the color is removed. It is used primarily either to color gray hair without changing the color of the remaining pigmented hair or to make gray hair a color that the person prefers to the natural gray. In general the coloring materials used to obtain semipermanent hair coloring are the penetrating type but they are gentler on the tissues and require no peroxide developer.
Temporary hair colorings differ from the permanent and semipermanent colorings in that they deposit color on the cuticle of the hair shaft, have no lasting effect on the hair color and are washed out by shampooing. In general temporary hair coloring materials are either rinses, highlighting shampoos or materials that can be applied to the hair in the form of powders, creams, or sprays.
Hair treating materials that are applied to the hair as a liquid may be any of these types:
These materials have various viscosities and flow rates that may vary with temperature.
There are two general ways in which liquids are applied to the hair to be treated. One may be called an all-over application process of which coloring shampoos and rinses are typical examples. This method has been used satisfactorily for certain types of hair treating materials which are relatively nonirritating to the scalp, nondamaging to the hair and which do not have critical time periods that must be observed in order to get satisfactory results. Many hair treating materials do not satisfy these criteria and are therefore applied in the other method which may be called a step-wise or progressive method, i.e., the treating liquid is aplied successively or progressively to small sections of the hair until the entire operation of treating the entire head of hair therewith has been completed. Various methods are already known for effecting this progressive application of a hair treating liquid to the hair. Beginning some four decades ago color was first applied with a swab. This was followed by the bowl and brush method in which the liquid to be applied was prepared in an open bowl and applied by means of a brush that was dipped into the liquid in the bowl and then moved to the section of the hair that was ready to receive the liquid where it was applied by brush strokes primarly in the direction from the scalp toward the ends of the hair. A more rapid method of applying hair treating liquids to the hair came with the use of a squeeze bottle having an externally threaded cylindrical neck on which a sectioning and disensing attachment or applicator is screwed. This attachment comprises a body having an internally threaded cylinder or collar to be screwed on the neck of a squeeze bottle projecting outwardly in one direction and an elongated projection extending outwardly in the opposite direction, e.g., a frustum of a cone or the like, having a tapered passageway for liquid passing completely through it. The hollow projection is referred to inthe art variously, e.g., as a tip or knife. A bottle and attachment of this type is shown in Levie U.S. Pat. No 2,794,440 for hair waving solutions. An operator is able to form successive sections of a customer's hair with such a device by holding the squeeze bottle as a handle and using the tip in the same way that a rattail comb is used, although Levie shows the use of a rattail comb anyway. Such a section of the hair, which may be about 1/4 inch up to 1 1/2, or even 3 to 4 inches, wide and ordinarily not more than about 1/8 inch thick, is referred to variously in the art as a lock, strand or tress of hair. After the operator has formed such a strand of hair in this way, it is held taut by one hand while the other hand squeezes the bottle to force a thin stream of liquid through the tip, e.g., onto the scalp along the near part line of the strand at the area to be treated for touch-ups or along a strand or tress for an overall treatment. The liquid must next be spread evenly and uniformly on only the new growth in touch-ups or through each strand or tress for overall treatment. The smooth tip of the applicator is worthless as a spreading device, or as a device to pick up excess dripping material near the hairline, so most operators effect the spreading of the liquid through a tress by the thumb and fingers and through the root areas on touch-ups and pick-up of excess liquid by the thumb of the band that holds the strand of hair being treated.
These methods produced heads of hair of uniform color that at one time were very fashionable whereas today women desire a more natural appearing head of hair which is characterized by somewhat darker shades underneath near the nape of the neck, somewhat lighter shades near the face and highlights on the surface, particularly when the hair has been exposed to sunlight. In order to accomplish this result on heads of virgin hair which lack the highlights and on heads of tinted and toned hair, various ways of dimensional hair coloring, hair painting, streaking, frosting, tipping and the like have been proposed. In these process the use of cotton swabs and brushes have been suggested for transferring the thick, viscous bleach material, e.g., a mixture of about 2 parts Basic White with 1 part by volume of hydrogen peroxide solution of suitable strength, to the portions of the hair to be treated. In hair painting or streaking, for example, the process of the prior art comprises parting the hair, combining it down and then painting the viscous or pasty material in narrow spaced stripes on the surface of the hair from about one half inch away from the scalp down at least on that portion of the hair which is supported by the head, starting near the front adjacent to the face and proceeding toward the back of the head. Since the viscous bleach material is too thick to flow and only surface hairs have it applied to them, the streaks developed by this process are lost to view if the hair is parted in a location different from that where it was parted for the painting operation. Another suggested procedure was to part off strands about 1/2 by 1 l to 2 inches, protect the hair behind each strand with heavy cream and/or cotton, placig a piece of foil under the strand and applying the viscous mixture to the strand starting about 1/2 inch away from the scalp and stopping short of the ends if they are damaged. After developing until the strands have reached golden blond stage, the viscous material is reapplied to the portion of the strand previously painted and to the ends until the hair is light enough when the action of the bleach is arrested. In hair frosting and tipping the prior art has taught parting off sections about an inch square, picking up tiny strands of about a dozen hairs each from a section with a fine rattail comb by a darning movement, laying them on a piece of foil placed over the remainder of the hair in the section, brushing the viscous bleach material on the tiny strands, folding the foil around these painted strands, and continue this procedure in checkerboard fashion until the desired area has been treated. After a period of time sufficient to develop the desired color in the painted strands the action is stopped by rinsing the strands individually in soapy water. Toner was applied if desired before shampooing to remove the material. For so-called blonde on blonde hair styling it was suggested to develop a desired blonde shade with toner on the whole head of hair, then section out spaced strands about 3/4 inch square in checkerboard fashion to cover the entire head, each strand being wrapped in aluminum foil, whereupon the second toner was applied to all the hair not covered including the base of the wrapped strands, allowed to develop about half and hour, then carefully rinsed and shampooed before removing the foils.
The present invention provides devices for parting the hair to form tresses and for efficiently transferring to and spreading such hair treating materials on the hair so as to control the area on which the materials are spread which overcome the disadvantages of devices used heretofore.